'In that respect there is a familiarity about it. The stadium, the size of the pitch, the condition of the pitch all these things are in their favour over other European teams.'

Ferguson is not expected to stray too much from the side whose victory last week was fully deserved even though they operated with a minority of possession.

Brazilian full-back Rafael is a majordoubt, with his manager claiming he would need to impress in training on Tuesday to stand any chance of ousting John O'Shea.

There must also be a possibility thatNani will get the nod ahead of Javier Hernandez, allowing Wayne Rooney to slot back into the lone striking role Ferguson prefers on occasions such as this.

The real boost for United is that they have choices to make. Ferguson himself cannot quite understand how a side that was weakened and derided so often during the early weeksof the season should reach this point still in with a chance of emulating their 1999 Treble-winning counterparts.

However, without question, they are now hitting top form, which Ferguson feels is crucial.

'Momentum is key,' he said. 'When you get that momentum it is difficult to knock you off your stride.

Crucial: Wayne Rooney was in the right place at the right time to beat Chelsea keeper Petr Cech last week

'Hopefully that is what will drive our players on. We are at an important time of year in that every game is a cup final now and the players are thriving on that.

'There were probably a lot of games earlier in the season when I might have been hesitant about making the changes I did on Saturday.

'Having the momentum, whoever comes in is carrying on the fight.'

The winners on Tuesday are likely to face Schalke in the semi-finals as the Germans hold a 5-2 advantage over Inter Milan.

In the other ties, Real Madrid are 4-0 up against Tottenham and Barcelona lead Shakhtar Donetsk 5-1.

'Can you imagine the Real Madrid v Barcelona semi-final? I'll be going to that,' said Ferguson.

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